End cap for a rail for a window covering



FIG. 1 is a top perspective view of an end cap for a rail for a window covering showing our design in a position of use;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof; and,

FIG. 5 is a right side view thereof, which is a mirror image of the left side view.

The rear of the end cap cannot be seen when the end cap is in use. The broken lines represent environmental structure that forms no part of the claimed design. 

CLAIM The ornamental design for an end cap for a rail for a window covering, as shown and described. 